Method of producing a yarn package



3,169,077 METl-ltltl) @F PRGDUQJHNG A YARN PACKAGE Richard MacHenry, Prospect Park, and Harry E.

Schwartz, Lester, Pa, assignors, by mesne assignments, to FMQ Corporation, San .lose, Calih, a corporation of Delaware No Drawing. Filed inn. 9, 196i, Ser. No. 81,258 9 Claims. (til. MIL-66) This invention relates to an improved yarn treating composition and a method of preparing a package of yarn treated with said composition. More particularly, it relates to a homogenous alkanol-latex treating composition for cellulosic yarn to be wound into packages and thereafter used for reinforcing rubber base material.

This application is a continuation-in-part of copending application Serial No. 44,256, filed July 21, 1960, and now abandoned.

Cellulosic yarns, particularly regenerated cellulose yarns, have been treated with rubber latex containing compositions to improve their adhesion to rubber base material, for example, in the manufacture of fabric reinforced tires, belts and hoses. The latex or aqueous dispersion of rubber has been applied to the yarn just prior to Winding the yarn onto a spool to form a package; however, upon application of an aqueous dispersion of rubber to low elongation, highly strained cellulosic yarn,

' An even more undesirable occurrence in the winding of water wet cellulosic yarn into packages is the loss of the original strength and elongation properties of the yarn produced by the shrinkage. Under such conditions, the customer purchasing yarn manufactured to provide properties of his specification does not receive a product meeting that specification. The application of an aqueous dispersion of rubber to the cellulosic yarn also causes a I certain amount of swelling. When the package dries out, it becomes soft and the yarn may slough off. If this occurs, the yarn breaks and production time is lost.

It is an object of this invention to provide an improved treating composition for cellulosic yarn to bewound into packages.

it is another object of this invention to provide a meth- 0d of packaging cellulose yarn which does not produce the loss of desirable yarn properties.

it is still another object of this invention to provide a method for producing an improved yarn package from wet treated cellulose yarn.

The foregoing and other objects are attained in accordance with this invention wherein the improved yarn treating composition comprises a homogenous mixture of a major proportion of a C C alkanol and a rubber latex adhesive in an amount suilicient to improve the adhesion of said yarn to rubber. The method of this invention comprises applying to cel-' lulose yarn in the unwound state the described treating composition, winding said yarn upon itself to form a package, and drying the package.

The alkanols suitable for this invention include for example, methanol, ethanol, n-propanol, isopropanol and t-butanol. These alcohols are suitable for the treating composition in that they are completely miscible with water, they provide satisfactory homogeneous mixtures with rubber latices, they do not degrade or swell the cellulose material, they have a sufficiently high vapor pressure to evaporate from the yarn in a reasonable amount of Bdfihfil'i. Patented Feb. 9, 1965 time, and they present little, if any, toxicity problems. The invention may be carried out with from at least 50 up to about 90% by volume of the alkanol in the homogeneous mixture; however, from about 70 to about is preferred.

The rubber latices of this invention include aqueous dispersions of finely divided particles of elastomeric materials including natural rubber and synthetic material having properties similar to natural rubber. Natural rubber includes, for example, caoutchouc, balata, gutta percha, pale crepe, etc. Synthetic rubber includes for example, polymers of vinyl pyridine, butadiene-1,3, isobutylene, 2-chloro-butadiene-l,3, isoprene, and the like, as well as interpolymers of these and similar materials with each other or with such interpolymerizable monomers as styrene, acrylonitrile, methacrylonitrile, methyl methacrylate, ethyl methacrylate, alkyl substituted vinyl pyridines, etc. Mixtures of any of the above rubber materials may be used in forming the latex, and rubber compounding materials such as pigments, softeners, vulcanizers, accelators and antioxidants are suitably incorporated in the rubber.

The rubber latex is a conventional aqueous dispersion of finely divided rubber and may include a small amount of dispersing agent and/or stabilizing agent. The finely divided rubber is usually present in the dispersion in an amount ranging from about 5 to about 50% by weight but preferably from 15 to 25%. The latex is generally supplied in a more concentrated form, for example, with from 49-50% dispersed rubber; however, more water is added to the aqueous dispersion to reduce the proportion of solids in the final mixture.

It is conventional for heat-curable, phenolic condensates to be incorporated with the rubber latices to promote adhesion. Generally, for this invention, the condensate is incorporated in an amount ranging from about 0.5 to about 5% by weight and preferably from about 1 to 3% by weight of the aqueous dispersion. The phenolic condensate is prepared in an aqueous dispersion by first partially condensing a phenol and an aldehyde in an aqueous solution in the presence of an alkali. The preferred phenolic compounds are substantially water-soluble polyhydric phenols having hydroxy groups in the meta positions, for example, resorcinol, orcinol, cresorcinol and m-xylorcinol. Other monohydric and polyhydric phenols may be used including phenol itself. The preferred aldehyde is formaldehyde or its polymers while other substantially water-soluble aldehydes such as acetaldehyde or furfural may be used in place of part or all of the formaldehyde. The heat-curable condensate may be prepared directly in the latex or separately; however, for the purpose of this invention it is preferred that it be formed in a separate solution and aged for from 4 to 10 hours at about 70 to 80 F. before mixing with the latex.

A typical method for the preparation of the finish or treating composition and its application to a yarn is set forth in the following example.

Example I 9,312 cc. of a stabilized concentrated latex, comprising an aqueous dispersion of finely divided resinous vinyl pyridine polymer (41% solids), were charged to a mixing vessel. 8,267 cc. of water were added to the same vessel and slowly mixed with the latex. 5,133 cc. of an aqueous dispersion of phenolic partial condensate were slowly added to the mixing latex.

The phenolic condensate was prepared by adding 40 cc. of a 17.5% aqueous sodium hydroxide solution to 5,568 cc. of water, then adding 256 grams of resorcinol to the alkaline water and dissolving it completely, then adding 377 cc. of formaldehyde to the mixture with stir- U ring for minutes, and then aging for 6 hours at 75 to 78 F.

The latex adhesive was mixed for 15 minutes to assure homogeneity and then aged for an hour. After this aging, 22.5 gallons of isopropanol were charged to the mixing vessel while the latex adhesive was slowly agitated. When the addition of isopropanol was complete, the homogeneous mixture was drained into a 55 gallon drum through a wire mesh screen and funnel.

The prepared treating composition was a homogeneous milkly liquid having the following percentage composition:

Percent by volume lsopropanol 79.0 Water 17.2 Solids 3.8

The liquid treating composition was applied to traveling single strands of tire cord type regenerated cellulose yarn by running the yarn over and in contact with a rotating roll which picked up the finish composition from a trough containing the liquid and deposited it on the traveling yarn. The treated yarn was then passed through a reciproeating guide and helically wound on a spool, mounted on a rotating spindle, into a yarn package. Freshly wound packages of the treated yarn were easily removed from the spindle and were first placed in a vented chamber for a few hours to take off the greater portion of the isopropanol vapors and then removed to an open space to completely dry.

The dry yarn packages formed as described above were free of end bulges and tightly wound, neat packages as compared to those wound from yarn treated with the usual aqueous latex-phenolic dip which exhibit bulging at the ends near the spool and are generally soft, mushy package usually diflicult to handle in further processing operations. On unwinding the treated yarn from the package it was found to have retained the strength and elongation properties for which it was manufactured.

The treating composition of this invention may contain other adhesive promoting chemicals and compositions which are compatible therewith. These adhesive promot-- ers can be incorporated in either the latex or alcohol prior to mixing or they may be incorporated into the finished blend.

The term yarn as used herein would include all types of narrow, elongated cellulosic material such as filaments, cords, strands, fibers, etc.

In addition to the use of the yarn treating composition of this invention as described in Example I, it has been found that it may be employed with excellent results for the application of rubber adhesive promoting material to shrinkable cellulose yarn and fabric material. The materials to which this invention has particular application are regenerated cellulose yarns which have been slashed and fabrics therefrom. Slashing has been broadly defined as a method of strengthening regenerated cellulose yarn wherein it is dried under tension. Usually, slashing defines an operation wherein the regenerated cellulose yarn is stretched many times its original length and dried in this stretched condition under tension. This type of yarn and fabric produced therefrom have a tendency to shrink greatly with the application of water.

Previously rubber adhesive promoting material has been applied to shrinkable cellulose yarn and fabric in the form of a rubber latex. tended to shrink the cellulose material so that it was nec essary to employ strong tension to hold the yarn or fabric while being treated with the rubber latex. The treating composition of this invention unexpectedly has been found to eliminate the necessity of holding the material to be treated under high tension since the treating composition does not tend to shrink the material.

An example of the treatment of regenerated cellulose fabric produced from slashed cellulose yarn is as follows.

The latex, being an aqueous fluid,

Example II A Woven fabric produced from 2200 denier, 1500 filament slashed tire yarn wet stretched 100% during its manufacture was passed from a roll through a bath of the liquid treating composition as described in Example l and then through a pair of squeeze rolls to remove excess fluid. The fabric was then permitted to dry without additional tension. On drying, it was found that the fabric had retained its original dimensions and no appreciable shrinking had occurred. The fabric was then used as a reinforcement for a rubber belt. Adhesion of the fabric to the rubber was found to be excellent.

Various changes and modifications may be made in practicing the invention without departing from the spirit and scope thereof and, therefore, the invention is not to be limited except as defined in the appended claims.

We claim:

1. A method for producing an improved yarn package comprising applying to a cellulosic yarn in the unwound state a homogeneous mixture comprising a C -C alkanol in a major proportion based on the volume of the mixture, and a rubber latex adhesive comprising an aqueous dispersion containing from about 5 to about 50% by weight of a finely-divided rubber and an adhesion promoting amount of a heat-curable phenolic condensate, winding said yarn upon itself to form a package, and drying the package.

2. A method for producing an improved yarn package comprising applying to regenerated cellulose yarn in the unwound state the homogeneous mixture comprising a C -C alkanol in an amount of from about 50 to based on the volume of the mixture, and a rubber latex adhesive comprising an aqueous dispersion of from about 15 to 25% by weight of a finely-divided, vinyl pyridine resin and from about 0.5 to 5% by weight of a heat-curable resorcinol-formaldehyde condensate, winding said yarn upon itself to form a package, and drying the package. I

3. A method for producing an improvedyarn package comprising applying to regenerated cellulose yarn in the unwound state a homogeneous mixture comprising isopropanel in an amount of from about 70 to about 8.0%

based on the volume of the mixture, and a rubber latex.

adhesive comprisingan aoueous dispersion of from about 15 to about 25 by Weight of a finely-divided vinyl pyridine moting amount of a heat-curable phenolic condensate, and

drying the cellulosic material to remove the alkanol and excess water. c

5. The method of claim 4 wherein the rubber latex comprises an aqueous dispersion ofa vinyl pyridine resin.

6. A method of applying rubber adhesive promoting material to shrinkable cellulosic yarn and fabric produced therefrom which comprises treating the cellulosic material with a homogeneous mixture comprising a C -C alkanol in an amount of from about 50 to 90% based on the volume of the mixture, and a rubber latex adhesive compris-' ing an aqueous dispersion of from about 15 to 25% by weight of a finely-divided'vinyl pyridine resin and from about 0.5 to 5% by weight of a heat-curable resorcinolformaldehyde condensate, and drying the cellulosic material to remove the alkanol and excess water.

7. The method of claim 6 wherein the alkanol is iso-' propanol.

8. The method of claim 6 wherein the cellulosic yarn is regenerated cellulose.

9. The method of claim 8 wherein the regenerated cellulose yarn is slashed yarn.

References Cited in the file of this patent UNITED STATES PATENTS -63 Addy et a1 Jan. 7, 1930 Branclwood Feb. 18, 1936 Isaacs Aug. 18, 1936 Merrill Dec. 9, 1941 Spanagel Apr. 7, 1942 Mighton July 17, 1951 Wilson Sept. 15, 1953 

1. A METHOD FOR PRODUCING AN IMPROVED YARN PACKAGE COMPRISING APPLYING TO A CELLULOSIC YARN IN THE UNWOUND STATE A HOMOGENEOUS MIXTURE COMPRISING A C1-C4 ALKANOL IN A MAJOR PROPORTION BASED ON THE BOLUME OF THE MIXTURE, AND A RUBBER LATEX ADHESIVE COMPRISING AN AQUEOUS DISPERSION CONTAINING FROM ABOUT 5 TO ABOUT 50% BY WEIGHT OF A FINELY-DIVIDED RUBBER AND AN ADHESION PROMOTING AMOUNT OF A HEAT-CURABLE PHENOLIC CONDENSAT, WINDING SAID YARN UPON ITSELF TO FORM A PACKAGE, AND DRYING THE PACKAGE. 